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991.
Céline Delerue Mary Hayhoe Muriel Boucart 《Journal of psychiatry & neuroscience : JPN》2013,38(5):317-324
Background
Visual scanning and planning of actions are reported to be abnormal in patients with schizophrenia. Most studies that monitored eye movements in these patients were performed under free-viewing conditions and used 2-dimensional images. However, images differ from the natural world in several ways, including task demands and the dimensionality of the display. Our study was designed to assess whether abnormalities in visual exploration in patients with schizophrenia generalize to active-viewing tasks in realistic conditions of viewing and to examine whether disturbances in action sequencing in these patients are reflected in their visual scanning patterns while executing natural tasks.Methods
We monitored visual scan paths in patients with schizophrenia and healthy controls. Participants performed several tasks in which they were asked to look at a realistic scene on a table (free-viewing) and perform 2 active-viewing tasks: a familiar task (sandwich-making) and an unfamiliar task (model-building). The scenes contained both task-relevant and task-irrelevant objects.Results
We included 15 patients and 15 controls in our analysis. Patients exhibited abnormalities in the free-viewing condition. Their patterns of exploration were similar to those of controls in the familiar task, but they showed scanning differences in the unfamiliar task. Patients were also slower than controls to accomplish both tasks.Limitations
Patients with schizophrenia were taking antipsychotic medications, so the presence of medication effects cannot be excluded.Conclusion
People with schizophrenia present a basic psycho-motor slowing and seem to establish a less efficient planning strategy in the case of more complex and unfamiliar tasks. 相似文献992.
Michael L. ALOSCO Andreana BENITEZ John GUNSTAD Mary Beth SPITZNAGEL Jeanne M. MCCAFFERY John E. MCGEARY Athena POPPAS Robert H. PAUL Lawrence H. SWEET Ronald A. COHEN 《Psychogeriatrics》2013,13(1):35-40
Background: Much attention has been paid to the prevalence and predisposition of the fat mass and obesity‐associated (FTO) gene to obesity, although only a few studies have characterized the extent to which this affects cognitive function. This study examined differences between risk allele carriers (i.e. FTO‐AC/AA) and non‐carriers (i.e. FTO‐CC) on indices of attention/executive function/psychomotor speed, memory, language, and visual‐spatial ability in a sample of older patients with cardiovascular disease. Methods: We recruited 120 older adults from an outpatient cardiology clinic who underwent blood draw and completed neuropsychological testing. Participants were classified into two groups: one for those who were homozygous for the non‐risk‐conferring allele (i.e. FTO‐CC) (n= 49) and the other for those who had at least one copy of the obesity risk‐conferring A allele (i.e. FTO‐AC/AA) (n= 71). Results: Mancova analyses adjusting for age and years of education revealed the FTO‐AC/AA group performed significantly worse on indices of memory (λ= 0.94, F(2, 115) = 3.58, P= 0.03, partial η2= 0.06). Follow‐up tests revealed a significant effect for the FTO‐AC/AA group, relative to the non‐carrier group, on encoding (i.e. California Verbal Learning Test Total Learning) and California Verbal Learning Test long‐delay free recall (P < 0.05). No such differences between FTO carriers and non‐carriers emerged on tests of attention/executive function/psychomotor speed, language, or visual‐spatial ability (P > 0.05 for all). Conclusions: These findings suggest that the FTO risk allele is associated with reduced memory performance, particularly on aspects of memory encoding and delayed recall. To elucidate underlying mechanisms, these findings will need to be replicated in larger samples that utilize neuroimaging. 相似文献
993.
994.
Brandy R. Matthews Chiung-Chih Chang Mary De May John Engstrom Bruce L. Miller 《Neurocase》2013,19(3):248-259
Recent functional neuroimaging studies implicate the network of mesolimbic structures known to be active in reward processing as the neural substrate of pleasure associated with listening to music. Psychoacoustic and lesion studies suggest that there is a widely distributed cortical network involved in processing discreet musical variables. Here we present the case of a young man with auditory agnosia as the consequence of cortical neurodegeneration who continues to experience pleasure when exposed to music. In a series of musical tasks, the subject was unable to accurately identify any of the perceptual components of music beyond simple pitch discrimination, including musical variables known to impact the perception of affect. The subject subsequently misidentified the musical character of personally familiar tunes presented experimentally, but continued to report that the activity of ‘listening’ to specific musical genres was an emotionally rewarding experience. The implications of this case for the evolving understanding of music perception, music misperception, music memory, and music-associated emotion are discussed. 相似文献
995.
Tony Ro Elizabeth Noser Corwin Boake Ruth Johnson Mary Gaber Alda Speroni 《Neurocase》2013,19(1):50-60
Preliminary assessments of the feasibility, safety, and effects on neuronal reorganization measured with transcranial magnetic stimulation (TMS) from Constraint-Induced Movement Therapy (CIMT) of the upper extremity were made in eight cases of subacute stroke. Within fourteen days of their stroke, patients were randomly assigned to two weeks of CIMT or traditional therapy. Baseline motor performance and cortical/subcortical representation for movement with TMS were assessed before treatment. Post-treatment assessments were made at the end of treatment and at three months after the stroke. The TMS mapping showed a larger motor representation in the lesioned hemisphere of the CIMT patients as compared to the controls at the three-month follow-up assessment. The enlarged motor representation in the lesioned hemisphere for hand movement correlated with improved motor function of the affected hand, suggesting a link between movement representation size as measured with TMS and functionality. These results suggest that TMS can be safely and effectively used to assess brain function in subacute stroke and further suggest that CIMT may enhance cortical/subcortical motor reorganization and accelerate motor recovery when started within the first two weeks after stroke. 相似文献
996.
We reviewed studies of the Wisconsin Card Sorting Test (WCST) in which the test was administered to subjects with and without evidence of focal frontal-lobe dysfunction. This review indicated that few studies had investigated the differential performance of normals and those with frontal dysfunction. The evidence that frontal patients perform more poorly than nonfrontal patients is weak. There is insubstantial evidence to conclude that the WCST is a measure of dorsolateral-frontal dysfunction. The clinical utility of the test as a measure of frontal-lobe dysfunction is not supported nor is the use of the test as a marker of frontal dysfunction for research purposes. 相似文献
997.
Mary M. Machulda V. Shane Pankratz Teresa J. Christianson Robert J. Ivnik Michelle M. Mielke Rosebud O. Roberts 《The Clinical neuropsychologist》2013,27(8):1247-1264
The objective of this study was to examine practice effects and longitudinal cognitive change in a population-based cohort classified as clinically normal at their initial evaluation. We examined 1390 individuals with a median age of 78.1 years and re-evaluated them up to four times at approximate 15-month intervals, with an average follow-up time of 5 years. Of the 1390 participants, 947 (69%) individuals remained cognitively normal, 397 (29%) progressed to mild cognitive impairment (MCI), and 46 (3%) to dementia. The stable normal group showed an initial practice effect in all domains which was sustained in memory and visuospatial reasoning. There was only a slight decline in attention and language after visit 3. We combined individuals with incident MCI and dementia to form one group representing those who declined. The incident MCI/dementia group showed an unexpected practice effect in memory from baseline to visit 2, with a significant decline thereafter. This group did not demonstrate practice effects in any other domain and showed a downward trajectory in all domains at each evaluation. Modeling cognitive change in an epidemiologic sample may serve as a useful benchmark for evaluating cognitive change in future intervention studies. 相似文献
998.
Robert L Findling Booil Jo Thomas W Frazier Eric A Youngstrom Christine A Demeter Mary A Fristad Boris Birmaher Robert A Kowatch Eugene Arnold David A Axelson Neal Ryan Jessica C Hauser Daniel J Brace Linda E Marsh Mary Kay Gill Judith Depew Brieana M Rowles Sarah McCue Horwitz 《Bipolar disorders》2013,15(6):669-679
999.
Adam L Boxer David S Knopman Daniel I Kaufer Murray Grossman Chiadi Onyike Neill Graf-Radford Mario Mendez Diana Kerwin Alan Lerner Chuang-Kuo Wu Mary Koestler Jill Shapira Kathryn Sullivan Kristen Klepac Kristine Lipowski Jerin Ullah Scott Fields Joel H Kramer Bruce L Miller 《Lancet neurology》2013,12(2):149-156
1000.
Mary Iampietro Deborah A. G. Drabick Rachel K. Kessler 《The Clinical neuropsychologist》2013,27(7):1166-1185
Executive function (EF) deficits in schizophrenia (SZ) are well documented, although much less is known about patterns of EF deficits and their association to differential impairments in everyday functioning. The present study empirically defined SZ groups based on measures of various EF abilities and then compared these EF groups on everyday action errors. Participants (n?=?45) completed various subtests from the Delis–Kaplan Executive Function System (D-KEFS) and the Naturalistic Action Test (NAT), a performance-based measure of everyday action that yields scores reflecting total errors and a range of different error types (e.g., omission, perseveration). Results of a latent class analysis revealed three distinct EF groups, characterized by (a) multiple EF deficits, (b) relatively spared EF, and (c) perseverative responding. Follow-up analyses revealed that the classes differed significantly on NAT total errors, total commission errors, and total perseveration errors; the two classes with EF impairment performed comparably on the NAT but performed worse than the class with relatively spared EF. In sum, people with SZ demonstrate variable patterns of EF deficits, and distinct aspects of these EF deficit patterns (i.e., poor mental control abilities) may be associated with everyday functioning capabilities. 相似文献